I love our robotic probes and eyes in the sky like Hubble and Chandra that DO advance scientific knowledge more than the high-cost, low return Space Station or the proposed trillion-dollar Dubya manned mission to Mars.

Even more impressive science telescopes await that exponentially improve on the 1970s generation(back when Hubble was designed) or the 1990s upgrades.

There is a danger that all the science will be scrapped for preserving funding for the "prestige" of "Man to Mars". Astronauts still have tremendous policy clout, even clout enough to have 5 times as many "qualified astronauts" on payroll as there are foreseeable missions for them..

If anyone ever tries selling you the water=life on Mars, manned mission is but a prelude to colonizing Mars - give them a reality check. Three things.

1. No nitrogen. None detected in any appreciable quantity as free atmosphere or fixed nitrogen in minerals. Nitrogen is indispensible to life and human existence. Any person on Mars would have to bring enough along to sustain whatever they breath or living plants and animals from Earth used as food. Right now, the cost of transporting enough is prohibited except for what a sort-duration expedition would use.

2. Other indispensibles to a presence there that would have to be launched and landed at a price of 50,000 a pound. The list is long.

3. No technology for the power source needed to sustain life with electricity, heating. Other than nuclear reactors.

Cedar, I'm not trying to pick a fight here (well not a insult-fest like on the political boards), but come on! Manned exploration is the end goal, is it not? Spain didn't send un-manned probes across the Atlantic did they? It's about embiggening the human soul. If NASA had sent an unmanned probe to take pictures of the Moon, as opposed to sending Buzz and the gang, would that have had even 1/1000th the cultural impact? If all our research had gone into figuring out how to send a camera on a rocket, would the wonderful spin-offs from the space program have been developed? No. Manned exploration is a perfectly cromulent use of tax monies.

In response to your specific points:

1. "No nitrogen." already addressed by Nick. Beyond that, who's to say we won't find a practical solution for low levels of nitrogen between now and any attempt at terraforming?

2. "Other indispensibles to a presence there that would have to be launched and landed at a price of 50,000 a pound." Yeah, and 8 megs of computer memory still costs about $1000 and always will, right? Aluminum is more valuable than gold, right?

3. "No technology for the power source needed to sustain life with electricity, heating. Other than nuclear reactors." Um... this one is pretty much self-refuting, right? Flying machines are mere fancy. Other than planes.

Nick - Because the atmosphere is so thin, less than 100th the Earths, the 3% that is there is not thought to be extractable without building an industrial-size compression-cryogenic factory (operating at less than 1/100th the efficiency, of an earth facility, requiring an enormous energy source, with no ready cooling water, or replacement components handy) bigger than the throw-weight and landing capacity of two dozen "Mars-sized" spacecraft. NASA bean counters did the financials on it (getting enough nitrogen to live out there) and as a result of the realization of cost - conspicuously omit any discussion of nitrogen from their talk of promoting water=life or "exciting future Mars colonies".

Hope for finding nitrogen in minerals looked for by Mars probes has so far come up without any. Plenty of sulphur, chlorine, O2. Few carbonates. No nitrogen in the form of nitrates or nitrites detected. (so far).

Here's Eta Carinae, our local candidate for Most Likely to Explode mentioned in the article. And it's somewhere between 7,500 and 10,000 light-years away. Any nearer, if it blows you might get a suntan at midnight in Australia. You wouldn't need an X-ray machine, either.

Fortunately, it's just far enough away to not produce much environmental impact here if and when the end comes. But a couple of thousand light-years closer, we would be toast.

One of the many weird things about this star is that it's rotating at a fantastic rate for something this large. It may be that centrifugal force is holding the star up against gravitational collapse, so it just sputters along with all sorts of strange goings on—lasers, x-rays, mini-explosions, extreme magnetic and tidal phenomena, and vast amounts of dust and gas expelled at tremendous velocity—a sort of slow-motion supernova.

I don't know what you might think, but this is one of the most awe-inspiring pictures of a natural phenomenon that I've seen. Here are clouds with newly-forged elements pouring out of a kind of cosmic anvil.

That would be funny - we cripple the global economy in the name of Climate Change, get starvaton depravation riots anarchy facist control.. just in time for the earth's atmosphere to be burnt away by some star few have even heard of.

I'd certainly hope not. Manned *exploration* is an incredibly stupid idea, given any foreseeable technology. We *might* need to ship people around if we find a good planet for them and for some weird reason decide to colonize it, but even then that's not a given.

If all our research had gone into figuring out how to send a camera on a rocket, would the wonderful spin-offs from the space program have been developed?

Even if we assume that planning to send men to the Moon was somehow a requirement for getting those spinoffs, the fact remains that the actual *act* of sending them there didn't get us anything but a feeling of pride. In other words, we'd have been better off if we'd figured out how to send men to the moon, then decided against it and spent the remaining billions of unmanned missions.

who's to say we won't find a practical solution for low levels of nitrogen between now and any attempt at terraforming?

Both amino acids and DNA are nitrogen-based. Let me know when you find a "practical solution" for the basis of all forms of life.

Yeah, and 8 megs of computer memory still costs about $1000 and always will, right? Aluminum is more valuable than gold, right?

Computers became better because there was demand for better information processing. There is not currently, not is there likely to ever be, any significant demand for Martian real estate.

"No technology for the power source needed to sustain life with electricity, heating. Other than nuclear reactors." Um... this one is pretty much self-refuting, right?

Only if you forget that Mars has no sources of fuel for those reactors.

"Other indispensibles to a presence there that would have to be launched and landed at a price of 50,000 a pound." Yeah, and 8 megs of computer memory still costs about $1000 and always will, right? Aluminum is more valuable than gold, right?

High tech true believers always love their chip RAM argument, ignoring that one rapidly advancing sector of science does not equate to exponential improvements or efficiencies in other areas of science.

Cancer is not 1 thousand times more curable than it was in 1970. Cars that got 15 MPG in 1973 do not get 300,000 MPG now. Current orbital throw weight, in constant dollars, is far more expensive now than it was in the Titan II, Delta II, Saturn V era.

It sounds good, though!

Even if it is a logical fallacy. Computer affordability and capabilities have enormously improved and lowered costs by a thousandfold - therefore, similar benefits and savings in my Cable TV/Satellite bills, health care costs - will happen any second, now.

I wasn't joking Palladian. The gamma rays from a supernova of Eta Carinae would not affect Earth, specifically because of our atmosphere.

The possible Eta Carinæ hypernova or supernova could affect Earth nearly 7,500 light years away, but would not likely affect humans directly, who are protected from gamma rays by the atmosphere. The damage would likely be restricted to the upper atmosphere, the ozone layer, and spacecraft, including satellites, and any astronauts in space. At least one scientist has claimed that if the star were to explode, "it would be so bright that you would see it during the day, and you could even read a book by its light at night".